To improve communication efficiency and avoid information distortion, the market of telephone conferences booms in recent years and the telephone conference is widely used in various enterprises. The telephone conference is a new way of conference mode in which a telephone is used as a tool and a telephone line is used as a carrier for the conference. However, communication efficiency of the telephone conference is not high. For example, if a participant wants to describe a graph, a lot of words are needed.
A face-to-face (F2F) conference is much more efficient comparing with the telephone conference. In the F2F conference, a participant may express ideas clearly and intuitively by marking or writing on a board. However, it is hard to do so in the telephone conference.